Posted
by
Soulskill
on Wednesday December 26, 2012 @01:49PM
from the don't-have-a-cow dept.

Tests on milk from several different farms across the U.K. have turned up evidence for a new strain of MRSA — bacteria which have evolved resistance to common antibiotics. As long as the milk is properly pasteurized, it poses no threat to consumers, but anyone working directly with the animals bears a small risk of infection. According to The Independent,
"The disclosure comes amid growing concern over the use of modern antibiotics on British farms, driven by price pressure imposed by the big supermarket chains. Intensive farming with thousands of animals raised in cramped conditions means infections spread faster and the need for antibiotics is consequently greater. Three classes of antibiotics rated as 'critically important to human medicine' by the World Health Organization – cephalosporins, fluoroquinolones and macrolides – have increased in use in the animal population by eightfold in the last decade."

Settle down you two. You do realize that the term 'scientists' is broadly encompassing? People that work for the evil industry. People whose moral compass shines brightly through the evil fog of the world (that's IT, no more caffeine this morning).

They don't live under volcanoes and play with obese felines. Well, most of them anyway.

First of all, bacterial resistance genes turn out to me much more complex than previously thought. Many resistance genes have evolved on cassettes [wikipedia.org] which have the ability to evolve irrespective of the host bacterial genome. So they are selected to hang around, even in the absence of the initial selection factor.

Further, these cassettes can be transmitted to OTHER bacteria even without antibiotic selection and annoyingly enough, tend to get lumped together into multiple antibiotic resistant bacteria. So, we've let the cat out of the bag - it was inevitable although we managed to make it a bigger problem faster than need be.

TL;DR antibiotic resistance is going to be around a long time whether or not we use the antibiotics. Scientists aren't all greedy douchebags. There are more things in heaven and earth, dear Slashdotters, Than are dreamt of in your philosophy.

If each type of bacterial pathogen responded only to a narrow spectrum antibiotic, then when you got sick from a bacterial infection the lab would have to assay your blood to figure out which of the millions of bacteria in your system were actually causing the problem, then get you the right medicine. And the moment one of the pathogens mutates, the antibiotic would have less of an effect on it. So add up the expense of the lab work, the delays in treatment that would cause, the stock of custom pharmaceuticals that every pharmacy would have to carry, and it turns out that broad spectrum antibiotics are a whole lot cheaper and overall more effective.

Or to follow on to your suggestion of cocktails, what makes you suppose that any one cocktail wouldn't act exactly as a broad spectrum antibiotic? If a cocktail reduces the probability to P^2, (P^2)>0 is still true, so resistance is still possible.

The problems of resistance are not caused because the antibiotics are broad spectrum, but primarily by the proliferation of under-dosed environments. If you're going to use an antibiotic, it has to be present in a sufficient dose for an appropriate duration to actually kill all of the pathogens. A too-small dose, or a course of treatment that is ended early for any reason, will leave you with some bacteria that survived due to a low-level of resistance. Their offspring will thrive, and some of them will go on to offer higher resistance if your antibiotic treatment resumes.

If you're going to give it to cows, it should be done in response to a specific pathogen, and they should be given the full dose and course of treatment. Their waste should be kept away from other animals that might pick up the infection. But recognizing an infection in a cow, then isolating and treating it is expensive, so it doesn't get done as a first choice.

Please note that I found that in a quick Google search. In this case, an antibiotic-susceptible organism jumped into pigs, became methicillin resistant. OK, that's not cows, but that shows me that the concern is based in real science.

Bacteria don't care where they live, as long as it's a suitable environment. In any such environment, if regularly exposed to antibiotics, they could develop resistance. This is true in food animals, humans, or petri dishes in the laboratory.

For you to make that assertion, I can only assume that either you are (a) uninformed or (b) a shill for Big Pharma, who make megatons of money off dumping antibiotics into the food chain.